The explosion of information now available relating to a wide variety of topics ranging from business to entertainment has driven the development of technology capable of providing this information to various selected groups and individuals. Once the information is conveyed from a source to a destination, the information is often categorized and stored either by individuals or by service organizations for subsequent retrieval of selected information.
Regardless of the particular form of received information, or the character of the storage media, it is often desirable to identify information of interest and extract that information from the incoming data stream for subsequent storage. This procedure optimizes the use of the storage media while also increasing the efficiency of the user in assimilating the information. Thus, the user interested in ascertaining knowledge relative to a particular area is exposed to the most relevant information from a wide variety of sources without being inundated with extraneous facts, figures, and advertisements. Similarly, a user may select a particular audio or video program for recording from continuously broadcast information so that valuable time is not wasted viewing or listening to unwanted information.
Many people no longer “tune-in” to a single broadcast from beginning to end. Instead, people often interleave their viewing or listening with “channel surfing” and “ad zapping” or “filtering” of information. Filtering is commonly called “ad zapping” but is used herein to refer to elimination or avoidance of advertisements or other repetitive information, such as repeated news footage or the like. Surfing, as used herein, refers to searching over time and/or available information channels for “interesting” information.
A number of prior art systems have recognized the problem of eliminating extraneous information prior to recording for subsequent retrieval and review. Many of these systems are limited to use with video information (often in combination with audio information), such as a television broadcast, and are not easily adaptable to other forms of information.
Many of the systems designed for use with audio/video (AV) information rely on prior marking or coding of the information for subsequent identification by a recording device. For example, a television broadcast may contain information relative to the program characteristics and content such as the starting and ending times, the type or content of the program, a program guide summary, a classification, a rating, or the like. This additional information may be included when the signal is originally broadcast, but is typically added by an annotation service. The signal is received and decoded and may be used to control any of a number of devices. For example, closed captioning information may be decoded to provide a textual transcript of the audio information, or the decoding receiver may limit what type of programs are viewed. The signal may also be utilized to automatically record particular programs on preselected channels via control of a video cassette recorder (VCR) and VCR recording tape cassette. Annotation services have been relied upon to facilitate prior art systems which provide surfing functions.
Reliance upon an annotation service requires the viewer to subscribe to the service and forces the viewer to explicitly select a menu item which ultimately corresponds to an approximate time/channel slot. This is a continuing expense for the viewer and may not support all of the channels which the viewer receives. In addition, the interesting material, such as a sports broadcast during the nightly news, may not be considered a “programming unit” by the annotation service so it would not be given an identifier which could be used by such systems. Furthermore, the interesting information may be broadcast on other channels or time slots and would not be identified.
Other prior art systems and methods which are designed primarily to eliminate recording of commercials (zapping) during a program broadcast rely on a change in amplitude of the video and/or audio signal components to control the recording of the information. The recording device monitors the incoming signal while recording and detects commercials by the characteristic video fade and/or audio fade between a program segment and a commercial. When a commercial is detected, the recording is paused so that the unwanted information is not recorded. Some prior art systems pause for a predetermined period of time (i.e. 15 or 30 seconds) after detecting a fade (or eliminate material between two fades separated by a standard advertisement interval) to avoid recording the advertisement. These systems rely on non-intrinsic characteristics of the broadcast signal which may lead to incorrect blanks in the recording of the desired program material. For example, an artistic fade in the middle of a program broadcast may be mistaken for a fade prior to an advertisement resulting in an undesirable 30 second blank in the recorded material. In addition, these approaches are limited to the elimination of advertisements and would be difficult to adapt to elimination of other “uninteresting” information from the incoming information stream, such as repetitive news footage. Furthermore, as such systems become more prevalent, broadcasters may reduce or eliminate the fades altogether to defeat operation of these systems so that advertisements reach their intended audience.
Another approach found in prior art systems designed to provide automatic recording of a particular television program of interest, requires the user to enter an index code into a VCR which is decoded to determine the broadcast channel, program starting time, and program duration. Since these systems do not monitor the actual broadcast signal being received, once recording begins, it continues for the duration specified regardless of the particular content of the signal. These systems are subject to recording errors resulting from minor modifications to the programming schedule of the television stations. Such minor schedule changes often occur to accommodate important news broadcasts or the like.
One alternative approach used to eliminate advertisements includes adding control information to the recording so that the advertisements are skipped when the recording is replayed. This avoids lost information due to an erroneous indication of an advertisement but requires the user to wait while the recording is fast-forwarded through the advertisement. Since this approach also relies on audio/video fades; it could easily be defeated by broadcasters when the economic incentive becomes great enough. Another approach offered by at least one television manufacturer provides a “real-time” zapping function which allows the viewer to scan other channels for 30 seconds before automatically returning to the original channel, so as to avoid a standard length advertisement.
Prior art AV editing systems have utilized the highly constrained structure of various news programs to segment a broadcast based on recognizing predetermined logos and faces of newscasters which are broadcast repeatedly. After receiving and recording a newscast or other structured program, these systems attempt to identify the various segments by separating the individual frames into regions and searching for the previously identified logos or faces. The segments are then classified and archived for use in future programs.